It is known in the art to equip a machine part of this kind with a glass fiber element to allow the measurement of different physical parameters. By doing so, a survey of the parameters becomes possible by using the fiber Bragg grating (FBG) method. By this method temperatures as well as strains of the machine arrangement can be monitored. An example of an arrangement of the generic kind is disclosed in US 2010/0158434 A1.
For doing so it is necessary to connect a glass fiber with the component. For surveying temperatures it is essential that a thermal coupling between the glass fiber and the machine arrangement is established. For monitoring strains it is necessary to mechanically connect the glass fiber with the component to be monitored.
Specifically in the latter case problems arise because the glass fiber is normally equipped with a plurality of coaxially arranged cover layers. A typical construction employs a cladding arranged around the glass fiber (core) itself; the cladding is coated by a coating layer. Then, strengthening fibers (made e.g. from aramid) are arranged at the outer circumference of the coating. Finally the strengthening fibers are cased by a hollow cylindrical cable jacket.
When a glass fiber element of this type is connected with the component a certain elasticity is immanent between the glass core and the component. Thus, specifically the measurement of strains is problematic due to the elasticity. This is specifically a problem when the component is not even or flat but if it has a spherical shape. This is typical in the case of a part of a bearing, specifically of a roller bearing.
US 2002/0118908 A1 shows the connection of an axial end of a glass fiber with substrate by means of glass material.
It is an object of the present invention to propose a machine arrangement of the above mentioned kind which is designed in such a manner that a contact is established between the glass fiber core and the component which is as stiff as possible. By doing so it is aimed to monitor physical properties, especially of strains in the component, with a high degree of precision. Thus, specifically a proper measurement of stresses should become possible even at curved surfaces of the machine arrangement as it is typical in the case of bearing rings.